Income Taxes - Changes in Reserves for Unrecognized Income Tax Benefits (Detail) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Income Tax Disclosure [Abstract] | ||
| Beginning balance | $ 35 | $ 35 |
| Additions based on current year tax positions | 106 | 0 |
| Ending balance | $ 141 | $ 35 |